Method of catalyzing oxygen-initiated free-radical polymerization and catalysts used therein

ABSTRACT

A class of new oxygen-activated free-radical polymerization catalysts, comprising specifically-defined autoxidizable cyclic hydrocarbons together with cobalt(II) compounds, is disclosed. A method of catalyzing an oxygen-initiated free-radical polymerization reaction using these catalysts is also disclosed.

This is a division, of application Ser. No. 290,908, filed Aug. 7, 1981,now U.S. Pat. No. 4,395,361.

TECHNICAL FIELD

The present invention relates to new oxygen-activated free-radicalpolymerization catalysts and a method for catalyzing a free-radicalpolymerization reaction using these materials.

BACKGROUND OF THE INVENTION

Objects tend to be particularly vulnerable at their surfaces. Thesurfaces of objects left in the open bear the brunt of the sun, rain,fog, dew, ice and snow. Under these conditions iron rusts, wood rots androad surfaces crack and disintegrate, just to name a few of the possibleconsequences. Even sheltered objects, such as those found in the home,suffer the wear of daily use; scratches, dents and abrasions, at theirsurfaces. To prevent or to minimize such damage, coatings designed toprotect surfaces are frequently applied. Coatings can also be used todecorate articles: to add color, luster, or to smooth out roughness orirregularities caused in the manufacturing process. Thus, in selecting asurface coating for a particular object there is a constant balancingwhich must go on between providing the necessary and appropriateprotection and decoration functions. A wide variety of surface coatingsis available, e.g., wallpaper, plastic sheets, chrome and silverplating. However, one of the most economical and versatile coatings ispaint, which can be applied to any surface, however awkward its size orshape, by one process or another.

Most paints contain liquid resinous or polymeric materials, known asbinders. It is this component which, after conversion to a solid throughthe paint's drying process, provides a surface film having the necessaryattributes of adhesion, flexibility, toughness and durability. Paintscan generally be subdivided into two broad categories: convertible andnon-convertible coatings. A convertible coating is a paint in which thebinder is either a polymer precursor, a monomer or a partiallypolymerized material. Upon addition of a suitable initiator or exposureto radiant energy, such as ultraviolet or infrared radiation, themonomeric or partially polymerized component of the paint undergoes apolymerization reaction in which the binder is converted from a liquidor a soluble state into an insoluble solid material film.Non-convertible coatings, in contrast, do not undergo curing or chemicalconversion reactions when they dry. For these paints, film formationinvolves loss or evaporation of a volatile solvent or dispersion mediumand the concomitant deposition of the solid binder material; it iscritical that this deposition be both uniform and continuous. SeeBoxall, et al., Concise Paint Technology, Chemical Publishing, New York,1977, especially pages 29-57; and Turner, Introduction to PaintChemistry, Chapman and Hall Ltd., 1967, especially pages 95-107.

BACKGROUND ART

Polymerization reactions involving simple monomers, i.e., vinyl cyclicacetals, in the presence of oxygen and cobalt salts, to producepolymeric materials are well-known in the art. See, for example,Hochberg, J. Oil and Colour Chemists Assoc., 48, 1043-1068 (1965) andU.S. Pat. No. 3,190,878, issued June 27, 1965, British Specification No.916,563, published Jan. 23, 1963, and German Specification No.1,148,033, published May 2, 1963, all assigned to E. I. duPont deNemours & Co. The reaction of itaconic acid with vinyl acetate to formpolyvinyl itaconate is also known. Akashi, Kogyo Kagaku Zasshi, 66, 156(1963). Polymerization reactions of acrylic-terminated oligomers,initiated through the use of ultraviolet light, have been disclosed,Prane, Polymer News, 4, 239-241 (1978). The use of benzaldehyde, in theabsence of oxygen, as an initiator for the free radical polymerizationof methyl methacrylate has been disclosed. Imoto, et al., J. Poly. Sci.,17, 385-392 (1979).

U.S. Pat. No. 4,244,850, Mylonakis, issued Jan. 13, 1981, describes apaint composition containing preformed aqueous emulsion acrylatecopolymer particles to which have been attached ethylenicallyunsaturated side chains. The acrylate copolymer, formed by emulsionpolymerization, is made from butyl acrylate, methyl methacrylate andmethacrylic acid. The unsaturated side chain is attached to thepreformed particles in the emulsion via a post reaction of the freecarboxylic acid groups with glycidyl methacrylate.

In formulating a paint, especially an interior wall paint, the keycharacteristics to be kept in mind, in addition to aesthetics, areconvenience of use, durability and ease with which the painted surfacemay be cared for. Further, when formulating a solvent-based paint, it isdesirable to have a high solids content. Paints with low solids contenthave increased amounts of solvent; this is generally consideredundesirable by consumers since ultimately the solvent just evaporatesoff. The paint should have excellent hiding properties (one-coat hidingis best); it should form a film which is stain resistant and easy toclean; it should have a high degree of surface continuity; and, finally,it should be durable, strong and resistant to wear.

SUMMARY OF THE INVENTION

The present invention relates to a new class of oxygen-activatedfree-radical polymerization catalysts which consist essentially ofmixtures of peroxide-decomposing transition metal catalysts, such as acobalt(II) compound, together with hydrocarbon compounds selected fromthe group consisting of ##STR1## and mixtures thereof, wherein each R₃is hydrogen, methyl, phenyl or COOH; R₄ is C₁ -C₂₀ alkyl or alkenyl; andn is from 1 to 10. These catalysts are especially useful in the paintand plastic compositions claimed in concurrently-filed U.S. patentapplication Ser. No. 290,918, Bush and Robbins, "Agents for PreparingCross-Linked Polymers and Paint and Plastic Compositions ContainingThese Agents", incorporated herein by reference.

The catalysts are used in oxygen-initiated free-radical polymerizationreactions whereby a resin material, capable of free-radicalpolymerization, is exposed to oxygen in their presence.

DETAILED DESCRIPTION OF THE INVENTION Polymer Precursor Materials

The essence of the present invention resides in a class of agents forpreparing cross-linked polymers; these agents, when reacted underappropriate conditions, undergo a cross-linking polymerization reactionforming a strong, durable polymeric film which is the basis of the paintand plastic compositions defined herein.

These agents are made up of two components: a major proportion of a lowmolecular weight backbone, and a minor proportion of mono- ordisubtituted olefinic groups pendant from that backbone. It is preferredthat the ratio, by weight, of pendant groups to backbone is from about0.05:1 to about 1:1, most preferably from about 0.1:1 to about 0.5:1.The backbone segment of the agent is selected from the group consistingof polyacrylates, polymethacrylates, polyesters, polyurethanes,polycarbonates, polyepoxides, polyvinyls, polystyrenes, or mixturesthereof, having a molecular weight of from about 1,000 to about 10,000;the preferred backbones for agents of the present invention beingpolycarbonates and, especially, polyacrylates. The precise backbonestructure to be used in a particular application is chosen based on themechanical strength, environmental resistance, and facility to performpost-oligomer chemistry (i.e., the ability to attach functional groups)required.

Examples of such backbone materials and procedures for synthesizing themare disclosed in Boxall, et al., Concise Paint Technology, ChemicalPublishing Co., Inc. New York, 1977, pages 29-57, incorporated herein byreference. Thus, for example, acrylic resins are polyvinylidenecompounds having the general formula

    --CH.sub.2 --CXY].sub.n,

wherein X commonly may be H, CH₃, C₂ H₅, and Y is usually COOH orCOOCH₃. Epoxy resins are cross-linked polymers derived from reactionsinvolving the epoxide or oxirane grouping ##STR2## Epoxy resins may beproduced by the reaction of bisphenol and epichlorhydrin. Polyurethaneresins are polymers containing the urethane group, ##STR3## within themain polymer backbone; they are formed by the reaction of isocyanates,R-NCO, with hydroxyl compounds. Preferred polycarbonates have thestructure: ##STR4##

The pendant groups are mono- or di-substituted olefinic groups, with theolefinic substituents being unpolymerized. To be useful in the presentinvention, the pendant groups should be susceptible to free radicalpolymerization and polymerize at an acceptable rate, upon appropriateinitiation, at room temperature in an oxygen atmosphere. Preferredpendant groups have a polymerization rate constant (measured at 70° C.)between about 10×10⁻⁴ and about 1000×10⁻⁴, especially between about10×10⁻⁴ and about 600×10⁻⁴, more preferably from about 60×10⁻⁴ to about600×10⁻⁴, moles^(-1/2) liter^(1/2) minute⁻¹. Particularly preferredpendant groups are those selected from the group consisting ofmono-methyl itaconate, 4-allyl-2-methylenesuccinate(beta-allylitaconate), 1-vinyl-2-methylenesuccinate(alpha-vinyl itaconate),p-vinylbenzoic acid, monovinyl maleate, methyl methacrylate,4-vinyl-2-methylenesuccinate(beta-vinyl itaconate),N-phenyl-2-methylenesuccinimide, substitutedN-phenyl-2-methylenesuccinimides and mixtures thereof; vinyl and allylitaconates, especially alpha-vinyl, beta-vinyl and beta-allylitaconates, are particularly preferred pendant groups.

The polymerization rate constant (K') of a specific monomer or, as usedherein, pendant group is equal to the rate of disappearance of theparticular monomer (rate) divided by the product of the initialconcentration of that monomer in solution (M) and the square root of theconcentration of azobisisobutylnitrile (AIBN) in the system beingtested. ##EQU1##

The rate is determined by heating a solution of monomer (pendant group)and AIBN at 70° C. and determining the change in concentration ofmonomer with time (mole/liter minute), using chlorobenzene as thesolvent under an argon atmosphere. K' is usually determined with monomerconcentrations in the range of from about 0.02 to about 2 mole/liter,while the concentration of AIBN is about 10 mole percent of the monomerconcentration. For example, the polymerization rate constant fordimethyl itaconate was determined in the following manner. Achlorobenzene solution containing 2.23 mole/liter dimethyl itaconate,0.23 mole/liter azobisisobutylnitrile, and 2.0 mole/liter dimethyladipate (internal standard for gas chromatographic analysis) wassubjected to three freeze-pump-thaw cycles, using liquid nitrogen tocool the sample and argon as the inert gas. After all the air had beenreplaced with argon, the reaction solution was placed in a bath at 70.0°C. and the disappearance of dimethyl itaconate was followed by gaschromatography until 20% of the dimethyl itaconate had polymerized. Aplot of time vs. concentration of dimethyl itaconate yielded the ratedata: rate (in mole/liter minute) is the slope of the plot. K' can thenbe calculated using equation (1).

The following table illustrates the polymerization rate constants of arange of pendant groups; some falling inside and some falling outsidethe scope of the present invention.

    ______________________________________                                        POLYMERIZATION RATE CONSTANTS OF                                              PENDANT GROUPS (AT 70° C.)                                             (X 10.sup.4 mole.sup.-1/2 liter.sup.1/2 minute.sup.-1)                        Alpha-allyl itaconate                                                                              24                                                       vinyl succinate      26                                                       beta-allyl itaconate 34                                                       allyl maleate        35                                                       dimethyl itaconate   38                                                       vinyl octanoate      54                                                       mono-methyl itaconate                                                                              107                                                      alpha-vinyl itaconate                                                                              111                                                      p-vinylbenzoic acid  113                                                      vinyl maleate        114                                                      methyl methacrylate  173                                                      phenyl alpha-methylenesuccinimide                                                                  495                                                      beta-vinyl itaconate 563                                                      vinyl chloride       8,480                                                    vinyl acetate        8,608                                                    methyl acrylate      18,944                                                   ______________________________________                                    

Materials with polymerization rate constants below the defined rangepolymerize too slowly to be practical for use in paint or plasticcompositions, while the materials with higher polymerization rateconstants (e.g., methyl acrylate, vinyl chloride, and vinyl acetate)polymerize in a rapid and uncontrolled manner, making their useunfeasible.

Preferred agents of the present invention (i.e., those having apolyacrylate backbone and vinyl itaconate or allyl itaconate pendantgroups) have the formulae ##STR5## wherein R₁ is hydrogen or methyl; R₂is hydrogen or an alkyl substituent; R₃ is vinyl or allyl; a is fromabout 10 to about 100; b is from about 0.1a to about a; and c is fromabout 1 to about 20. Most preferred agents are those having the formulae##STR6## wherein R₂ is C₁ -C₅ alkyl; R₃ is vinyl or allyl; a is fromabout 10 to about 100, preferably from about 16 to about 48; b is fromabout 0.1a to about a, preferably from about 6 to about 12; c is fromabout 1 to about 5; and d is from about 0.3b to about 0.5b, preferablyfrom about 2 to about 6. Preferred beta-vinyl itaconate pendant groupsare described in concurrently-filed U.S. patent application Ser. No.290,907, Bush, "4-vinyl-2-methylene-butanedioic Acid Compounds",incorporated herein by reference.

The agents of the present invention may be prepared, using conventionalmethods, for example, in the following manner:

A reaction flask is continually flushed with inert gas (e.g., argon) andcharged with the following ingredients: the backbone resin, the acidchloride of the olefinic pendant group, and ethyl acetate. To thissolution is added dropwise, with vigorous stirring, an ethyl acetatesolution of an organic base capable of taking up the liberated HCl andalso of catalyzing the reaction. Insoluble inorganic bases, such ascalcium carbonate or ion exchange resins, can be used instead of theorganic base, but they additionally require a base catalyst, such aspyridine or triethylamine. Where an inorganic base is used, the olefinicpendant group is added dropwise to a well-stirred dispersion of theinsoluble base, the backbone resin and the base catalyst in ethylacetate. After the base addition is complete, the reaction is worked upimmediately in the following manner: the reaction mixture is filtered toremove precipitated amine hydrochloride, washed with saturated sodiumbicarbonate to remove any unreacted acid chloride pendant groups or freeHCl, and concentrated to remove the ethyl acetate solvent.

Catalysts

The polymer precursor materials of the present invention are usefullycombined with catalyst materials (i.e., latent radical initiators)which, when initiated in an appropriate manner, as by introduction ofoxygen, ultraviolet radiation, heat or light into the system, cause theprecursor materials to undergo free radical polymerization forming across-linked polymer film. Although any type of catalyst effective in afree radical polymerization reaction may be used, when formulating paintcompositions, it is especially preferred to combine the polymerprecursor materials of the present invention with a catalytic amount ofan oxidative catalyst sufficient to cross-link from about 2% to about60%, preferably at least about 10%, most preferably at least about 20%of the pendant groups of the precursor within about 48 hours uponexposure to air at a temperature of about 20° C. Compositions comprisingthe precursor materials and such oxidative catalysts generally containfrom about 0.5% to about 5%, by weight, of the catalyst.

An especially preferred catalyst for use in the present invention is atwo-component system consisting of: (a) a specifically-definedhydrocarbon component and (b) a peroxide-decomposing transition metalcatalyst. In order for a hydrocarbon to function effectively in suchcatalyst systems, it first has to be capable of autoxidation to form ahydroperoxide. In a hydrocarbon R₁ R₂ R₃ CH, the selection ofsubstituents R₁, R₂ and R₃ so as to lower the dissociation energy of thecarbon-hydrogen bond will be essential to performance in the catalystsystem; thus hydrocarbons which readily autoxidize are most useful inthe catalysts of the present invention. However, it is not onlysufficient to have a hydrocarbon which autoxidizes rapidly, but it isalso essential that the intermediate hydroperoxide formed decomposehomolytically at a rate faster than it is being formed. The hydrocarboncomponent is most preferably selected from the group consisting of##STR7## and mixtures thereof, wherein each R₃ is hydrogen, methyl,phenyl or COOH; R₄ is C₁ -C₂₀ alkyl or alkenyl; and n is from 1 to 10.The aromatic groups may be substituted; however, replacement of theoxygens with nitrogen atoms will significantly reduce the efficacy ofthese catalyst systems. Preferred hydrocarbon components are thosehaving the formulae: ##STR8## and mixtures thereof. A preferred class ofhydrocarbon components is the 2-alkyl substituted 1,3-dioxolanes, with1,3-bis(1,3-dioxolan-2-yl)propane being especially preferred.

The peroxide-decomposing transition metal catalyst component ispreferably a cobalt(II) compound. Such compounds are well-known in theart and most frequently are cobalt(II) salts of carboxylic acids or a2,4-pentanedione complex of cobalt(II). Examples of such compoundsinclude cobalt(II) dipivalolylmethane, cobalt(II) acetylacetonate,cobalt(II) acetate, cobalt(II) decanoate, cobalt(II) naphthenate, andmixtures thereof. In forming these preferred catalysts for use in thepresent invention the mole ratio of hydrocarbon component to transitionmetal catalyst (cobalt(II) compound) is from about 5 to about 5,000,most preferably from about 10 to about 1,000.

Although the catalysts, defined above, are particularly useful incombination with the precursor materials of the present application,they have a more general use in catalyzing oxygen-initiated free radicalpolymerization reactions using any suitable precursor materials. Infact, these catalysts provide a generalized method for catalyzingoxygen-initiated free radical polymerization reactions wherein a resinmaterial capable of free radical polymerization is exposed to oxygen inthe presence of an effective amount of the catalyst consistingessentially of: (a) hydrocarbon catalyst compound, as defined above, and(b) a peroxide-decomposing transition metal compound, as defined above,especially a cobalt(II) compound. In such a polymerization reaction theratio, by weight, of resin to catalyst (i.e., the combination ofhydrocarbon and transition metal compound) is from about 5:1 to about200:1. As used above, the phrase "effective amount" indicates an amountof catalyst material used to effectively catalyze the cross-linkingpolymerization reaction. For any given reaction, the precise amount ofcatalyst required will be dependent upon the reaction conditions, theparticular resins to be used, and the speed and completeness of thereaction desired; this amount for any given set of reaction materialsand conditions is easily determined by one skilled in the art.

The catalyst system, as defined above, may additionally contain astorage stabilizer component. Storage stabilizers (i.e., apolymerization inhibitor) act to assure that the free radicalpolymerization will not occur until the resin and catalyst mixtures havebeen exposed to oxygen or another appropriate initiator; however, theyshould not interfere with the operation of the catalyst system whenpolymerization is desired. Such storage stabilizers generally act byscavenging and tying up any itinerant free radicals which may be presentin the system. Thus, for example, in formulating a paint composition ofthe present invention, the resin, the catalyst and a storage stabilizerare all included in the containers of paint; this assures that thepolymerization will not take place until the paint is applied to asurface and exposed to oxygen. A particularly useful storage stabilizeris tetraphenylverdazyl, having the formula ##STR9## Useful stabilizersalso include tetraphenylverdazyl derivatives wherein one or more of thephenyl groups are replaced by substituted phenyl or C₁ -C₁₀ alkylgroups. Another group of useful stabilizers is the low molecular weightoximes disclosed in U.S. Pat. No. 4,261,872, Eammons, et al., issuedApr. 14, 1981, incorporated herein by reference. Such stabilizers may becombined with the catalysts, as defined above, to form a stabilizedoxidation catalyst system. When used in this way, such stabilizedsystems generally contain from about 0.05% to about 20%, preferably fromabout 1% to about 15%, of the storage stabilizer and from about 99.95%to about 80%, preferably from about 85% to about 99%, of the oxidationcatalyst. Such stabilized oxidation catalysts may also be combined withthe resin of the present invention to form compositions which are stableupon storage in an oxygen-free environment but which undergo acontrolled free radical polymerization reaction upon exposure to oxygen.Such compositions generally contain from about 80% to about 90% of theresin component, from about 0.005% to about 2% of the storage stabilizercomponent, and from about 0.05% to about 5% of the oxidative catalyst.

Paint Compositions

The polymer precursor materials described in the present application areespecially adapted for use in formulating paint compositions. Thecompositions are applied to the surface, where the polymer precursormaterials polymerize in situ, forming the paint film. Thus, the key isto use a polymer precursor which will polymerize in situ, uponappropriate initiation, in an oxygen atmosphere at room temperature. Theparticular polymer precursor (e.g., the nature and amount of its pendantgroups), initiator or storage stabilizer selected will affect the speedand completeness of the in situ polymerization. These paint compositionsexhibit outstanding aesthetic and performance properties, includingvolume efficiency (solids content as high as 85 to 90%, as compared with25 to 50% for commonly-used paints), high levels of surface continuity,stain resistance, and durability, as well as strength and resistance towear. The paints may be formulated either as emulsion-based or assolvent-based compositions.

In an emulsion-based paint, the resin is in the form of small discretedroplets dispersed in an aqueous phase. Examples of suitable emulsifyingagents include, but are not limited to, alkanolamides, amine oxides,alkyl sulfonates, alkylbenzene sulfonates, ethoxylated alcohols,ethoxylated fatty acids, ethoxylated alkyl phenols, ethoxylated andpropoxylated amines, ethoxylate and propoxylate block copolymers,glycerol esters, glycol esters, lanolin-based derivatives, lecithinderivatives, olefin sulfonates, quaternary ammonium surfactants,ethoxylated sorbitan esters, ethoxylated alcohol sulfates, ethoxylatedalkylphenol sulfates or phosphates, alcohol sulfates, fatty acid estersulfonates, alkylammonio acetates, alkylammonio hexanoates, alkylammoniopropane sulfonates, and fatty acid sulfates. An emulsion-based paintcomposition comprises:

(a) from about 10% to about 60%, preferably from about 15% to about 50%,by weight, of solid pigment particles;

(b) from about 15% to about 60%, preferably from about 20% to about 55%,by weight, of the film-forming agents described above;

(c) an amount, preferably from about 0.1% to about 10%, of an oxidativecatalyst sufficient to cross-link from about 2% to about 60% of thependant groups of said film-forming agent within about 48 hours uponexposure to air at a temperature of 20° C.;

(d) from about 0.5% to about 10%, by weight, of an emulsifying agent oragents;

(e) from 0% to about 25% of an organic cosolvent; and

(f) the balance water.

The paint compositions of the present invention are more frequentlyformulated as solvent-based paints. Such solvent-based compositionscomprise:

(a) from about 10% to about 60%, preferably from about 15% to about 50%,by weight, of solid pigment particles;

(b) from about 15% to about 60%, preferably from about 20% to about 55%,by weight, of a film-forming agent as described above;

(c) an amount, preferably from about 0.1% to about 10%, of an oxidativecatalyst sufficient to cross-link from about 2% to about 60% of thependant groups of said film-forming agent within about 48 hours uponexposure to air at a temperature of 20° C.; and

(d) from about 5% to about 45%, preferably from about 10% to about 30%,by weight, of a solvent for said film-forming agent.

The paint compositions are formulated in the conventional manner knownin the art; the particular amounts and components included in any givencomposition being dependent upon such factors as the likely serviceenvironment of the paint, the desired life expectancy of the coatng, themethod of application, the color, the surface finish, the desired dryingtime and, the desired cost of the formulation.

Solvents used in the paint compositions are volatile liquids added inorder to dissolve the resin component and to modify the viscosity of thecoating. To be effective, the solvent must fulfill certain criteria. Itmust yield a solution of viscosity to suit the storage and applicationrequirements of the paint. It should have the correct evaporation rateand it must deposit a film with optimum characteristics. It should alsohave an acceptable odor, minimal toxicity, and a reasonable cost. Informulating a paint with convertible resins, as is the case in thepresent invention, solvents are primarily added to enable the coating tobe applied by the appropriate technique. The two most importantcharacteristics of solvents for use in paint compositions are solventpower (ability to dissolve specific resins) and evaporation rate (therelative speed with which they leave the coating after application).Solvents conventionally known for use in paint compositions are usefulin the compositions herein; such solvents include, but are not limitedto, 2-ethylhexyl acetate, amyl acetate, ethyl acetate, isobutyl acetate,n-propyl acetate, Ektasolve® DB (diethylene glycol monobutyl ether),Ektasolve® DE acetate (diethylene glycol monoethyl ether acetate),Carbitol® acetate, Cellosolve® acetate, Texanol® ester alcohol(2,2,4-trimethyl pentanediol-1,3-monoisobutyrate), ethanol, and mixturesthereof. Solvents particularly useful in the paint compositions of thepresent invention include ethyl acetate, amyl acetate, propylene glycol,mixtures of ethyl acetate and propylene glycol, mixtures of ethylacetate, ethanol and propylene glycol, and mixtures of ethyl acetate,propylene glycol and water.

The paint compositions of the present invention may also, optionally,contain a storage stabilizer, as described above, to inhibit the freeradical polymerization reaction while the paint is stored in itscontainer, but permitting the reaction to take place once the paint isapplied to the surface. Such stabilizers are generally contained in thepaint compositions in amounts of from about 0.005% to about 5%, byweight, of the total composition. A particularly useful storagestabilizer is tetraphenylverdazyl, having the formula ##STR10##

A pigment, which can be organic or inorganic in origin, may be definedas a solid material in the form of small discrete particles, which isincorporated into, but remains insoluble in, the paint medium. A pigmentconfers a number of attributes to a paint film, notably color andopacity, while influencing the degree of resistance of the film tolight, contaminants and other environmental factors, as well asmodifying the flow properties of the liquid paint. Pigments may beeither organic or inorganic in origin. Inorganic pigments may beconveniently classified by color. Those useful in the present inventioninclude white pigments, such as titanium dioxide, zinc oxide, antimonyoxide, while lead, and basic lead sulfate; red pigments, including rediron oxide, red lead, cadmium red, and basic lead silicochromate; yellowpigments, including lead chromates, zinc chromates, yellow iron oxides,cadmium yellow, and calcium plumbate; green pigments, including chromiumoxide and lead chrome green; blue pigments, such as Prussian blue andutramarine blue; and black pigments, such as black iron oxide. Ofcourse, mixtures of various pigments may be used. The pigments are usedin combinations and amounts based on factors such as color and colorintensity desired, intended use of the paint, and the identity andproperties of other components used in the paint formulation. Titaniumdioxide, because of its non-toxicity and its very high stability, is aparticularly preferred pigment for use in the paint compositions of thepresent invention. Metallic pigments useful in the present inventioninclude aluminum powder, zinc powder and lead powder. Organic pigmentswhich may be used in the paint compositions include red pigments, suchas toluidine red, and arylamide red; yellow pigments, such hansa yellowand benzidine yellow; green pigments, such as pigment green D; bluepigments, such as phthalocyanine blue; and black pigments, such ascarbon black. Pigment extenders (e.g., calcium carbonate, silica) mayreplace part of the pigment used; this is especially true whererelatively high pigment levels (e.g., 40-60 % of the compositions) arebeing used.

There is a further class of paint additives that are also insoluble inthe paint medium but which impart little or no opacity or color to thefilm into which they are incorporated. These materials are known asextenders and they are all of inorganic origin. Extenders areincorporated into paints to modify the flow properties, gloss, surfacetopography and the mechanical and permeability characteristics of thefilm. Extenders useful in the present invention include barytes,whiting, china clay, mica, and talc.

Dyes are exclusively of organic origin; generally, although notnecessarily, dyes and organic pigments are only incorporated into paintswhose prime function is decorative rather than protective.

Plasticizers may also be included in the paint compositions definedherein. The main function of a plasticizer is to increase and maintainfilm flexibility, particularly in paints based on binders which, in theabsence of plasticization, tend to be brittle. Plasticizers can eitherbe added physically to the paint composition, generally duringmanufacture, or they can be chemically incorporated into the polymermolecule by copolymerization techniques. Useful plasticizers includedibutyl phthalate, dioctyl phthalate, triphenyl phosphate, tricresylphosphate, trichloroethyl phosphate, butyl stearate, and chlorinatedparaffins.

Additional components, conventionally used in paint formulations, may beincorporated into the paint compositions of the present invention attheir art-established usage levels; such components include, but are notlimited to, drying accelerators; biocides, such as complex compounds ofphenol, formaldehyde and, less commonly, mercury; fungicides, such aszinc oxide, barium metaborate, organomercurials, organotin compounds,dithiocarbamates, and dichlorfluamide; antifouling agents, such asmetallic copper, copper suboxide, tributyl tin oxide and mercuric oxide;pigment dispersing agents; paint viscosity modifiers, such as naturalclays, thixotropic resins, and cellulose ethers; flatting agents; flowcontrol agents; anti-sag agents; surface conditioners; yield strengthagents; and pigment anti-settling agents, such as surface-active agents,most notably soya lecithin at levels of 1% of the pigment content.

Plastic Compositions

The polymer precursor materials of the present invention are alsobeneficially incorporated into plastic compositions. Such plasticcompositions exhibit very high levels of mechanical strength anddurability. The plastic compositions contain from about 20% to about99%, preferably from about 30% to about 90%, of the polymer precursormaterials as described above, or of the crosslinked polymers formed fromthese materials. In addition, these compositions may optionally alsocontain from about 0.1% to about 10%, especially from about 0.5% toabout 5%, of a free-radical polymerization catalyst, especially onewhich catalyzes the free radical polymerization of the resins uponexposure to heat, ultraviolet radiation or oxygen. Preferredoxygen-initiated catalysts include the mixtures of hydrocarbon compoundswith peroxide-decomposing transition metal materials, especiallycobalt(II) compounds, described hereinbefore. The plastic compositionsmay additionally contain components conventionally found in plastics attheir art-established usage levels. Examples of such components include,but are not limited to, extenders (e.g., chopped fiberglass), minerals(e.g., silica), plasticizers, anti-oxidants, hardeners, dyes, colorants,opacifiers or compounds to modify the mechanical, electrical, thermal,chemical or optical properties of the plastic.

The plastic compositions described herein may be manufactured and usedin a variety of physical forms for a variety of applications. Forexample, the resins may be polymerized, such as by an injection moldingprocess, and used as pre-formed sheets or shaped parts (such as in anautomobile or boat body). The plastics of the present invention areespecially well-adapted for use in reaction injection molding processes;such processes are described in detail in Milby, Plastics Technology,McGraw-Hill, Inc., 1973, pages 334-389, incorporated herein byreference. In a reaction injection molding process, the polymerprecursor and catalyst, in a liquid state, are injected through channelsinto a closed mold. The polymerization reaction is then initiated, and aplastic film in the desired configuration is formed.

In contrast, the resins may be used in the form of a liquid compositioncontaining the appropriate catalyst and, if desired, a storagestabilizer. The compositions may be applied as a film to, for example,floors or automobile exteriors, and will polymerize on exposure to theair forming a strong, durable protective coating.

As used herein, all percentages and ratios given are by weight, unlessotherwise specified.

The following non-limiting examples illustrate the present invention.

EXAMPLE I Resin Backbone Preparation

The backbone portion of the precursor materials described in the presentapplication may be prepared using procedures known in the art. SeeSorenson and Campbell, Preparative Methods of Polymer Chemistry, 2ndEdition, page 154. Methyl acrylate (MA)/hydroxyethyl acrylate (HEA) andmethyl acrylate/hydroxyethyl acrylate/acrylic acid (AA) backbonepolymers were made in the following manner, using a high pressure lab 3gallon reactor and the components described in the following table.

    ______________________________________                                        Ingredient       grams    moles    ml (21° C.)                         ______________________________________                                        9 MA:2HEA                                                                     Methyl Acrylate  3523     40.9     3380                                       Hydroxyethyl Acrylate                                                                          1056     9.1       960                                       Acrylic Acid     --       --       --                                                          4579     50.0     4440                                       Ethyl Acetate    6608     75.0     7340                                       Dodecyl Mercaptan (DDM)                                                                         324     1.6                                                 Azobisisobutyronitrile                                                                         41.1     0.25                                                (AIBN)                                                                        8 MA:3HEA:1AA                                                                 Methyl Acrylate  2870     33.3     2990                                       Hydroxyethyl Acrylate                                                                          1451     12.5     1320                                       Acrylic Acid      300     4.2       287                                                        9621     50.0     4597                                       Ethyl Acetate    6608     75.0     7340                                       Dodecyl Mercaptan (DDM)                                                                         324     1.6                                                 Azobisisobutyronitrile                                                                         41.1     0.25                                                (AIBN)                                                                        ______________________________________                                    

The reactor was first checked for water flow to the coil, jacket andcondenser. The reactor was then purged with nitrogen for 1 to 2 minutes.Condenser water was turned on and ingredient addition was begun. Half ofthe ethyl acetate was charged into the reaction flask and the mixer wasstarted. The monomers were then added in the following order: MA, HEA,AA. Residual monomer was washed into the reaction vehicle using ethylacetate. Next, DDM was added to the reaction mixture, followed by AIBNwhich was washed into the reactor with the remainder of the ethylacetate. The reactor was heated to 49° C., and, since the reaction isexothermic, the temperature was allowed to rise to 60° C. Thetemperature of the reaction flask was then maintained at 60±3° C. byadjusting the coil cooling water. When the reaction was complete (about1 hour), the reactor was heated to 75.5±2° C. and maintained at thattemperature for 4 to 6 hours to decompose the AIBN. The reactor was thencooled to room temperature and the reaction mixture was removed. Themolecular weight of the resin backbone formed ranges from about 2,000 toabout 8,000 and can be controlled by adjusting the level of DDM in thereaction mixture.

Capping Reaction of 9MA:2HEA Backbone Resin with Beta Vinyl ItaconylChloride

The 9MA:2HEA backbone resin, synthesized above, was capped, using betavinyl itaconyl chloride (B-VIC), to form a preferred resin materialdescribed in the present application. B-VIC was synthesized via thetransvinylation of itaconic acid with vinyl acetate; this process isdescribed in concurrently-filed U.S. patent application Ser. No.290,907, Bush, 4-Vinyl-2-Methylenebutanedioic Acid Compounds,incorporated herein by reference. The reaction and reagents utilized inthat procedure are described in the following table.

    ______________________________________                                         ##STR11##                                                                    (randomly mixed acrylate backbone)                                             ##STR12##                                                                     ##STR13##                                                                    (C.sub.2 H.sub.5).sub.3 N.HCl                                                 (A) = mixed acrylates                                                           Reagent    Function    Amount   Moles                                       ______________________________________                                        (9MA:2HEA)                                                                             backbone    96 g. solids                                                                             0.19 (moles OH)                               B-VIC    capping group                                                                             33 g.      0.19                                          Ethyl Acetate                                                                          solvent     500 ml.    5.7                                           Triethylamine                                                                          base catalyst                                                        9 g.     0.19                                                                 ______________________________________                                    

A two-liter, three-neck round-bottom flask was fitted with thefollowing: a Teflon stirring paddle, shaft and bearing for an overheadmechanical stirrer; a 250 milliliter addition funnel with a side arm; anargon inlet at the top of the addition funnel; a thermometer; and anargon outlet attached to a bubbler.

The flask was flushed with argon and an argon atmosphere maintainedduring the reaction. The backbone resin in ethyl acetate, B-VIC, andethyl acetate solvent were placed in the reaction flask. Vigorousstirring was begun and the drop-wise addition from the addition funnelof a solution of distilled triethylamine in an equal amount of ethylacetate was begun. The triethylamine was distilled through a 12-inchVigreux column at atmospheric pressure and the middle cut, boiling at80° C., was used. To promote good mixing and dispersion of thetriethylamine and to prevent gellation, it is important that theaddition of this solution be slow. The addition step took about 2 hours.During the addition of the triethylamine, the amine hydrochloride formedprecipitated as a white solid, giving the reaction mixture a whitecloudy appearance. Toward the end of the addition, a more muddyappearance developed as the reaction mixture darkened. At this point, ifthe color becomes intense, the addition of triethylamine solution shouldbe stopped. After the triethylamine addition is stopped or completed,the reaction should be worked up immediately.

The precipitated amine hydrochloride was filtered through a Buchnerfunnel with Whatman glass fiber paper using a lab aspirator (about 20 mmmercury). The filtration proceeded rapidly. The filter cake was thenwashed with 100 milliliters of ethyl acetate. A 10 milliliter aliquot ofthe ethyl acetate filtrate was concentrated on a rotovap and was usedfor an NMR spectrum. The rest of the solution was transferred to a 2liter separatory funnel and washed with an equal volume of saturatedsodium bicarbonate solution. An emulsion was formed and several hourswas required for a clean, distinct separation of phases. The mixture wasallowed to stand overnight to separate. The lower layer still containedsome insoluble polymer, but was easily separated from the upper layer.The lower layer consisted of the aqueous phase which was drawn away anddiscarded. The upper organic phase was drawn into a 2 liter Erlenmeyerflask and 100 grams of anhydrous magnesium sulfate was added and allowedto stand for half an hour. The magnesium sulfate was then filtered outthrough a Buchner funnel with glass fiber paper. The resulting ethylacetate solution was then concentrated on a rotovap (H₂ O) aspirator, 2mm mercury, 40° C.) to the desired solids level, approximately 79-85%solids. The solids level was determined by the following ASTM method ofevaporation at 100° C. for two hours: a sample of the concentrated resinwas accurately weighed (to 4 decimal places) into a glass Petri dish,placed in the oven at 100° C. for two hours, cooled to room temperatureand reweighed.

The resin was transferred to a bottle and stored under argon at 0° C. Itis important that oxygen be excluded to prevent premature polymerizationof the resin. The product was then analyzed by NMR (in CDCl₃) and IR(neat with residual ethyl acetate). In the infrared spectrum, the vinylgroup is seen at 1640 cm⁻¹. The NMR spectrum showed the following peaks(chemical shifts reported in δ):

    ______________________________________                                         ##STR14##                                                                     ##STR15##                                                                      3.67singlet 3H, (CO.sub.2 CH.sub.3).sub.9                                    ##STR16##                                                                      4.53                                                                        4.63                                                                          4.73doublets 2H, CHCH.sub.2                                                   5.00                                                                           ##STR17##                                                                      7.03                                                                        7.13                                                                          7.27quartet 1H, CHCH.sub.2                                                    7.37                                                                          ______________________________________                                    

Capping Reaction of 9MA:2HEA Backbone Resin with Beta Allyl ItaconylChloride

As in the previous procedure, the 9MA:2HEA backbone was capped usingbeta allyl itaconyl chloride to form a preferred resin material. Thereagents described in the following table were reacted in the manner ofthe previous procedure:

    ______________________________________                                         ##STR18##                                                                     ##STR19##                                                                      Reagent    Function    Amount   Moles                                       ______________________________________                                        9MA:2HEA backbone    318 g solids                                                                             0.64 (Moles OH)                               Beta-AIC capping group                                                                             120 g      0.65                                          Ethyl acetate                                                                          solvent     1 l.       10.2                                          Triethylamine                                                                          catalyst    64 g       0.64                                          ______________________________________                                    

After work-up in the manner of the previous procedure and rotovapping tothe desired solids level (approximately 75-85% solids), the resin wastransferred to a bottle and stored under argon at 0° C. The identity ofthe resin was confirmed by NMR and IR spectra.

Capping Reaction of (8MA:3HEA:1AA) Backbone Resin with Beta VinylItconyl Chloride

A preferred resin of the present application was synthesized using8MA:3HEA:1AA backbone resin, synthesized above, and beta vinyl itaconylchloride, using the procedure described below; the reaction and reagentsused in the reaction are given in the following table.

    ______________________________________                                         ##STR20##                                                                     ##STR21##                                                                          Reagent        Function  Amount  Moles                                  ______________________________________                                        (8MA:3HEA:1AA)                                                                             backbone    50 g. solids                                                                            0.135                                                                         (moles OH)                                 B-VIC        capping group                                                                             23.5 g.   0.135                                      Ethyl acetate                                                                              solvent     200 ml.   2.3                                        *Amberlyst A-21                                                                            ion exchange                                                                              64 g.     0.27                                                    resin to    (dry resin)                                                       take up acid                                                     Triethylamine (TEA)                                                                        catalyst    0.68 g.   0.0068                                     ______________________________________                                         *Amberlyst A21 (available from Rohm & Haas) is a weakly basic anionic         exchange resin intended for the absorption of acidic solutes from either      aqueous or nonaqueous media. The resin is furnished in the hydrated,          freebase form and the water must be removed ro replaced with ethyl acetat     prior to use.                                                            

A one-liter 3-neck round-bottom flask was fitted with the following: aTeflon stirring paddle, shaft and bearing for an overhead mechanicalstirrer; a 250-milliliter addition funnel with a side arm; an argoninlet at the top of the addition funnel; a thermometer; and an argonoutlet attached to a bubbler.

The ion exchange resin was conditioned by treating it with severalvolumes of methanol in a column, allowing the methanol to pass down at aflow rate of 4 bed volumes per hour. Further conditioning of themethanol-moist resin was then performed by passing several volumes ofethyl acetate through the resin bed at the same flow rate. The resin wasused wet in the ethyl acetate solution, although it may also be used ina dry state. In either case, it is imperative that no methanol remain inthe resin, due to its reactivity with beta vinyl itaconyl chloride. Ifit is desired to use dry resin, the ethyl acetate solvent may be removedusing reduced pressure on a rotovap at a temperature less than 75° C.

The flask was flushed with argon and an argon atmosphere was maintainedduring the reaction. The backbone resin in ethyl acetate, the ionexchange resin, triethylamine catalyst and the ethyl acetate solventwere placed in the reaction flask. Vigorous stirring was begun and asolution of B-VIC in an equal volume of ethyl acetate was added dropwiseto the reaction vessel from the addition funnel. The addition requiredabout 15 to 30 minutes. At the end of the addition, the reaction wasslightly exothermic (about 35° C.).

The reaction mixture was allowed to stir at room temperature under argonfor an additional 3 hours and was then worked up in the followingmanner. The ion exchange resin was filtered through a Buchner funnelwith glass fiber paper and washed with 200 milliliters of ethyl acetate.A 10 milliliter aliquot of the ethyl acetate filtrate was concentratedon a rotovap and used for an NMR spectrum. The rest of the solution wastransferred to a one liter separatory funnel and washed with an equalvolume of saturated sodium bicarbonate solution. An emulsion, whichrequired several hours to form a clean, distinct separation of phases,resulted. The mixture was allowed to stand overnight to separate. Thelower layer contained some insoluble polymer, but was easily separatedfrom the upper layer. The lower layer (the aqueous phase) was drawn awayand discarded. The upper organic phase was drawn into a one literErlenmeyer flask and 100 grams of anhydrous magnesium sulfate were addedand allowed to stand for one half hour. The magnesium sulfate was thenfiltered out through a Buchner funnel with glass fiber paper. Theresulting ethyl acetate solution was concentrated on a rotovap (H₂ Oaspirator, 20 mm mercury, 40° C.) to the desired solids level,approximately 75-85% solids. The solids level was determined by thefollowing ASTM method of evaporation at 100° C. for two hours: a sampleof the concentrated resin was accurately weighed (to 4 decimal places)into a glass Petri dish, placed in an oven at 100° C. for two hours,cooled to room temperature and reweighed.

The resin was then transferred to a bottle and stored under argon at 0°C. It is important that oxygen be excluded to prevent prematurepolymerization. The identity of the resin formed was confirmed by NMRand IR spectra.

EXAMPLE II

Using conventional procedures known in the art (see Sorenson andCampbell, Preparative Methods of Polymer Chemistry, 2nd Edition, page154) and the techniques described in Example I, additional resinmaterials of the present invention were synthesized as described below.

A poly(ethylene-co-trimethylolpropylene adipate) backbone resin wassynthesized as follows. The reaction flask was charged with 305 gramsadipic acid, 22.4 grams trimethylolpropane, 186 grams ethylene glycoland 8.6 grams p-toluenesulfonic acid monohydrate. The mixture was heatedat 120° C., under an argon atmosphere, overnight; 90 milliliters ofwater were collected in a Dean Stark trap. The resulting polyesterbackbone was analyzed for hydroxyl and carboxyl end groups by titration.

Similarly, a poly(ethylene-co-pentaerythritol adipate) backbone wassynthesized in the following manner. The reaction flask was charged with8.5 grams pentaerythritol, 93 grams ethylene glycol, 153 grams adipicacid and 4.3 grams p-toluenesulfonic acid. The mixture was heated at120° C., under argon, until the distillation of water ceased.

Vinyl itaconate-capped polyesters of the present invention can beprepared from the backbones synthesized above by either of two methods:(a) addition of itaconic anhydride to the backbone, forming the acidintermediate, followed by transvinylation with vinyl acetate; or (b) amore direct route by acylation with vinyl itaconyl chloride of the freehydroxyls on the backbone resin. For example, according to route (a),199 grams poly(ethylene-co-pentaerythritol adipate) polyester backbone,52 grams itaconic anhydride and 200 milligram hydroquinone were heatedat 90° C., under argon, for three hours. To the reaction flask was added700 milliliters vinyl acetate, 5 grams mecuric acetate and 1 gramconcentrated sulfuric acid. Refluxing was continued for 21/2 hours andthe final reaction mixture was worked up according to conventionalmethods.

Polycarbonate backbone resins may be prepared by conventional methodsfrom bisphenols or diols and phosgene or in a melt polycondensation withdiphenyl carbonate. For example, equal molar quantities of bisphenol A(25 grams) and diphenyl carbonate (24 grams) were mixed under argon andheated at 140° C. until the distillation of phenol ceased. A vacuum wasthen applied to remove residual phenol.

Another polycarbonate backbone was prepared by mixing 78 gramshexamethylene glycol, 72 grams diethyl carbonate and 0.25 grams sodiumand heating them at 110° C., under argon, until the distillation ofethanol ceased. The vinyl itaconate-capped resin of the presentinvention was then prepared from this backbone material using theitaconic anhydride-vinyl acetate route, described above.

Mixed acrylate backbones were also prepared using the same proceduredescribed for preparing methyl acrylate resins in Example I. The cappingreaction with vinyl itaconate was also carried out in the mannerdescribed in Example I. Using this procedure, the following backboneresins were prepared: 9 ethyl acrylate:2 hydroxyethyl acrylate:1 acrylicacid; 9 butyl acrylate:2 hydroxyethyl acrylate:1 acrylic acid; and 14methyl methacrylate:3 hydroxyethyl acrylate:3 acrylic acid. By way ofexample, the (14 MMA:3HEA:1AA) vinyl itaconate resin of the presentinvention was prepared as follows. The backbone resin was synthesizedusing the procedure described in Example I by reacting 50 grams methylmethacrylate, 12.5 grams 2-hydroxyethyl acrylate, 7.7 grams acrylicacid, 1 gram AIBN, 2 grams dodecanethiol and 50 milliliters ehtylacetate. This backbone resin was then capped using an excess ofalpha-vinyl itaconyl chloride in ehtyl acetate with an equal molaramount of calcium carbonate base, as described in Example I.

EXAMPLE III

High solids, solvent-based paint formulae of the present invention,having the compositions given below, were prepared in a conventionalmanner. The resin, titanium dioxide, silica and ethyl acetate componentswere thoroughly mixed together in a Cowles or flat blade mixer until thecomponents were well dispersed. The initiator system, i.e., thehydrocarbon peroxide precursor and cobalt(II) compound, were then addedinto the composition and mixed and dispersed gently. The flatting agentmay be added to the initial mixture or to the dispersed mixture beforethe initiator is added. The compositions, below, provided high solidspaint compositions which exhibited excellent covering characteristics,strength and durability.

    ______________________________________                                        Component           parts (by weight)                                         ______________________________________                                        Composition A        (8MA:3HEA:1AA) vinyl itaconate 35                        TiO.sub.2 (Rutile)  30                                                        Amorphous silica    5                                                         Micron-sized silica flatting agent                                                                5                                                         Ethyl acetate       23                                                        1,3-bis(1,3-dioxolan-2-yl)propane                                                                 2                                                         Cobalt naphthenate  0.1                                                       Composition B                                                                 (9MA:2HEA) vinyl itaconate                                                                        25                                                        TiO.sub.2 (Rutile)  40                                                        Amorphous silica    5                                                         Flatting agent (silica)                                                                           5                                                         Ethyl acetate       23                                                        1,3-bis(1,3-dioxolan-2-yl)propane                                                                 2                                                         Cobalt naphthenate  0.1                                                       Composition C                                                                 (8MA:3HEA:1AA) vinyl itaconate                                                                    35                                                        TiO.sub.2           30                                                        Amorphous silica    5                                                         Flatting agent (silica)                                                                           5                                                         Ethyl acetate       8                                                         Ethanol             8                                                         Propylene glycol    7                                                         1,3-bis(1,3-dioxolan-2-yl)propane                                                                 2                                                         Cobalt naphthenate  0.1                                                       Composition D                                                                 (9MA:2HEA)vinyl itaconate                                                                         30                                                        TiO.sub.2           30                                                        Calcium carbonate   5                                                         Amorphous silica    5                                                         Flatting agent (silica)                                                                           5                                                         Ethyl acetate       23                                                        1,3-bis(1,3-dioxolan-2-yl)propane                                                                 2                                                         Cobalt naphthenate  0.1                                                       ______________________________________                                    

Substantially similar results are obtained where the resin materialscontained in the above compositions are replaced, in whole or in part,by (8MA:3HEA:1AA) vinyl itaconate, (9MA:2HEA)vinyl itaconate,poly(ethylene-co-trimethylolpropylene adipate) vinyl itaconate,poly(ethylene-co-pentaerythritol adipate) vinyl itaconate, 9 ethylacrylate:2 hydroxyethyl acrylate:1 acrylic acid vinyl itaconate, 9 butylacrylate:2 hydroxyethyl acrylate:b 1 acrylic acid vinyl itaconate, 14methyl methacrylate:3 hydroxyethyl acrylate:3 acrylic acid vinylitaconate, (9MA:2HEA) beta-allyl itaconate, or resins having backbonesare previously described and wherein the pendant groups are selectedfrom mono- methyl itaconate, 4-allyl-2-methylenesuccinate,1-vinyl-2-methylenesuccinate, p-vinylbenzoic acid, mono-vinyl maleate,methyl methacrylate, N-phenyl-2-methylenesuccinimide and substitutedN-phenyl-2-methylenesuccinimides.

Substantially similar results are also obtained when the titaniumdioxide pigment component in the above compositions is replaced, inwhole or in part, by zinc oxide, antimony oxide, while lead, basic leadsulfate, red iron oxide, red lead, cadmium red, basic leadsilicochromate, lead chromate, zinc chromate, yellow iron oxide, cadmiumyellow, calcium plumbate, chromium oxide, lead chrome green, Prussianblue, ultramarine blue, black iron oxide, aluminum powder, zinc powder,lead powder, toluidine red, arylamide red, hansa yellow, benzidineyellow, pigment green D, phthalocyanine blue, carbon black, and mixturesthereof.

Similar results are also obtained wherein the hydrocarbon peroxideprecursor contained in the above compositions is replaced, in whole orin part, with ##STR22## or mixtures thereof.

Similar results also obtained where the cobalt naphthenate in the abovecompositions is replaced, in whole or in part, with cobalt(II)dipivaloylmethane, cobalt(II) acetylacetonate, cobalt(II) acetate,cobalt(II) decanoate, and mixtures thereof.

The compositions described above may also contain an effective amount ofa storage stabilizer component, such as from about 0.1 to about 1% oftetraphenyl verdazyl.

EXAMPLE IV

An emulsion-based paint formulation of the present invention wasprepared in the following manner.

Part 1

6.7 grams (8MA:3HEA:1AA) vinyl itaconate (about 85% solids)

6.7 grams TiO₂

1.8 grams propylene glycol

0.2 gram AMP-95 (2-amino-2-methyl-1-propanol, available from IMCCorporation)

The above components were mixed well with a flat blade high speed mixer.

Part 2

7.2 grams water

0.9 gram carbitol acetate (diethylene glycol monoethyl ether acetate)

0.5 gram nopcosperse 44 (dispersant for TiO₂ in aqueous systems,available from Diamond Shamrock)

0.1 gram DM-710 Igepal (dinonylphenoxypoly(ethyleneoxy) ethanol nonionicsurfactant commercially available from GAF Corp.)

0.05 gram DM-880 Igepal (dinonylphenoxypoly(ethylenoeoxy) ethanolnonionic surfactant commercially available from GAF Corp.)

The components of part 2 were mixed until all the surfactants weredissolved. Then, part 3, below, was added to part 2 in small portionswith stirring; the stirring was continued until the mixture was welldispersed.

Part 3

4 grams TiO₂

The part 2 plus part 3 mixture was then added gradually to part 1, withstirring, the stirring continuing until a homogenous mixture was formed.Finally, the initiator system (a mixture of about 0.5 part1,3-bis(1,3-dioxolan-2-yl)propane and 0.025 part cobalt naphthenate) wasmixed into the emulsion.

The emulsion paint formed by this procedure exhibits excellent coveringqualities, is high in solids, and is strong and durable under heavy wearconditions.

An additional emulsion-based paint formulation of the present inventionwas formulated as follows:

Part 1

10 grams 9MA:2HEA capped with allyl itaconate (70% solids)

0.1 grams ethoxylated sorbitan monoleate (20 ethoxylate groups persorbitan monoleate--Tween 80)

0.45 grams cobalt naphthenate (6% cobalt, from Sheppard Chemical Co.)

0.54 grams Lupersol 256 (2,5-dimethyl-2,5-bis(2 ethylhexanoylperoxy)hexane, Pennwalt Lucidal Co.)

These ingredients were brought to homogeneous solution.

4.0 grams of 1% aqueous polyethoxy-polypropoxy block copolymer (PluronicF87, Wyandotte BASF Co.) was added, and emulsified with high shearmixing.

Part 2

6 grams titanium dioxide

5 grams 1% aqueous Pluronic F-87

In forming part 2, the TiO₂ was blended into the aqueous Pluronicsolution until a smooth mixture resulted.

Part 2 was then added to Part 1 slowly and with hand stirring untiltransfer was complete, then the composition was subjected to high shearmixing until uniform.

EXAMPLE V

A paint composition, having the components listed below, was formulatedaccording to the method described in Example III. This paint was thencompared with a commercial latex paint (i.e., Sears Easy Living® paint)to determine their comparative properties.

    ______________________________________                                        Component             Weight %                                                ______________________________________                                        (8MA:3HEA:1AA) vinyl itaconate                                                                      35                                                      TiO.sub.2             40                                                      Ethyl acetate         22                                                      1,3-bis(1,3-dioxolan-2-yl)propane                                                                    2                                                      Cobalt naphthenate     1                                                      ______________________________________                                    

When applied to a wall and permitted to dry, the surface formed by thepaint of the present invention was smooth and continuous, whereas thesurface of the commercial paint was characterized by spaces in thematrix and the particulate nature of the latex. This was very clearlyseen when the two surfaces were viewed by scanning electron microscopeat a magnification of 500 X. This difference in film continuity carriesover into the macroscopic properties of enhanced durability, waterresistance and decreased permeability for the paint of the presentinvention.

The paint of the present invention was compared to the commercial paintin terms of stain resistance, using alkaline cleaners, on arepresentative variety of stains using the following procedure.

The paints were applied, using a thin film applicator, on 61/2 inch by17 inch scrub test panels so that the dried film thickness was about 2mils. The films were allowed to air dry and cure for one week. Stainswere then applied to each painted panel in a 21/2 inch strip widthwiseacross the panel in the center of the dry paint film. Quantities andtypes of stains applied were as follows: (a) oil stain--30 drops from aPasteur pipette; (b) crayon stain--red Crayola® crayon--21/2 inch bandat 200 gram pressure; (c) High Point® instant coffee (0.2 gram); (d)French's® mustard (0.2 gram); (e) ballpoint pen ink, Bic® (21/2 inchband, 200 gram pressure); (f) aluminum mar (21/2 inch band, 200 grampressure). The stains were allowed to set for 15 minutes. Using aGardner colorimeter, model XL-23, the L,a,b and Hunter whitness of bothstained and unstained paint portions were made. The samples were thenplaced in a scrub machine having a large sponge holder. The sponge wasmoistened and squeezed by hand and then was wet with 15 milliliters of acleaning solution made up of Mr. Clean®, commercially available from TheProcter & Gamble Company, in distilled water (weight ratio ofcleaner:water=1:64). On each sample the machine was permitted to run 5cycles back and forth. The Hunter whiteness readings of the paintsamples were then read again and were compared to the prescrub readings.

Using this procedure, the paint composition of the present inventionshowed a significant stain removal advantage vs. the commercial paintover the range of soils tested. Because the paint of the presentinvention provides a more continuous film, the staining substancescannot penetrate the surface and become entrapped, as they can in latexpaint; therefore, stains remain only on the surface of the paint of thepresent invention and stain removal is greatly enhanced.

The paint composition of the present invention also provided significantadvantages over the commercial paint in mar resistance, hardness andimpact tests using ASTM-established test procedures. Durabilityadvantages were seen in the improved washability (the paint compositionsof the present invention outscrubbed the commercial paint by 3 to 4times in ASTM scrub tests), and in excellent chemical resistance (i.e.,the paint compositions of the present invention were not removed byorganic solvents, such as acetone, or by full-strength alkalinecleaners).

EXAMPLE VI

Plastic compositions incorporating the technology of the presentinvention are illustrated by the following formulations.

    ______________________________________                                        Component             Weight %                                                ______________________________________                                        (8MA:3HEA:1AA) vinyl itaconate                                                                      75                                                      1,3-bis(1,3-dioxolan-2-yl)propane                                                                   4                                                       cobalt naphthenate    2                                                       miscellaneous components                                                                            balance                                                 (e.g., plasticizer,                                                           colorant, tetraphenyl                                                         verdazyl storage stabilizer,                                                  extender)                                                                     ______________________________________                                    

The components in the above table are combined, using conventionalmixing and dispersion techniques, to form a plastic precursor material.This material may be sold as is, to be formed or molded by the purchaserinto plastic sheets or molded plastic parts. The plastic formed exhibitsvery high strength and durability characteristics. The oxygen-initiatedcatalyst system in the above composition may be replaced by aheat-initiated catalyst system, and the composition may then be used ina conventional injection molding process to form shaped plasticarticles. Obviously, the above composition may also be preformed intosheets or molded plastic articles and may be sold or used in that form.In that case composition of the articles is essentially the same as thatgiven in the table except that the vinyl itaconyl resin precursors havereacted to form cross-linked polymers.

    ______________________________________                                        Component             Weight %                                                ______________________________________                                        (9MA:2HEA)vinyl itaconate                                                                           40                                                      1,3-bis(1,3-dioxlan-2-yl)propane                                                                    3                                                       cobalt naphthenate    0.15                                                    tetraphenyl verdazyl  0.1                                                     ethyl acetate         50                                                      miscellaneous components                                                                            balance                                                 (e.g., hardener,                                                              anti-oxidant, sheeting agent)                                                 ______________________________________                                    

The components described in the above table may be combined usingconventional mixing and dispersion techniques to form a plastic coatingcomposition. This composition may be applied to, for example, floors orautomobile bodies in a thin coat, polymerizing upon exposure to oxygen,forming a strong and durable transparent protective coating on thesurface.

In either of the above plastic compositions, the hydrocarbon componentof the catalyst system may be replaced, in whole or in part, by##STR23## and mixtures thereof.

In addition, the cobalt naphthenate, in either of the above compositionscan be replaced, in whole or in part, by cobalt(II) dipivalolylmethane,cobalt(II) acetylacetonate, cobalt(II) acetate, cobalt(II) decanoate,and mixtures thereof.

The resin material used in either of the above two plastic compositionsmay be replaced, in whole or in part, by (8MA:3HEA:1AA) vinyl itaconate,(9MA:2HEA) vinyl itaconate, poly(ethylene-co-trimethylolpropyleneadipate) vinyl itaconate, poly(ethylene-co-pentaerythritol adipate)vinyl itaconate, 9 ethyl acrylate: 2 hydroxyethyl acrylate: 1 acrylicacid vinyl itaconate, 9 butyl acrylate: 2 hydroxyethyl acrylate: 1acrylic acid vinyl itaconate, 14 methyl methacrylate: 3 hydroxyethylacrylate: 3 acrylic acid vinyl itaconate; (9MA:2HEA)beta-allylitaconate; or polymer precursor materials having the backbones givenabove but wherein the pendant group is replaced, in whole or in part, bymono-methyl itaconate, 1-vinyl-2-methylenesuccinate,4-allyl-2methylenesuccinate, p-vinylbenzoic acid, mono-vinyl maleate,methyl methacrylate, N-phenyl-2-methylenesuccinimide, substitutedN-phenyl-2-methylenesuccinimides, or mixtures thereof.

What is claimed is:
 1. A method of catalyzing an oxygen-initiated freeradical polymerization reaction by exposing a resin material, capable offree radical polymerization and comprising a major portion of a lowmolecular weight backbone with a minor portion of mono- or disubstitutedolefinic groups having a polymerization rate constant between about10×10⁻⁴ and about 1,000×10⁻⁴ moles^(-1/2) liter^(1/2) minute⁻¹ pendantfrom said backbone, to oxygen in the presence of an effective amount ofa catalyst consisting essentially of: (a) a compound selected from thegroup consisting of ##STR24## and mixtures thereof, wherein each R₃ ishydrogen, methyl, or COOH; R₄ is C₁ -C₂₀ alkyl; and n is from about 1 to10; and (b) a peroxide-decomposing cobalt(II) compound.
 2. A methodaccording to claim 1 wherein the ratio, by weight, of resin to catalystis from about 5 to about
 200. 3. A method according to claim 2 whereincompound (a) is selected from the group consisting of ##STR25## andmixtures thereof.
 4. A method according to claim 2 wherein thecobalt(II) compound is selected from the group consisting of cobalt(II)salts of carboxylic acids and a 2,4-pentanedione complex of cobalt(II).5. A method according to claim 4 wherein the cobalt(II) compound isselected from the group consisting of cobalt(II) dipivaloylmethane,cobalt(II) acetylacetonate, cobalt(II) acetate, cobalt(II) decanoate,cobalt(II) naphthenate, and mixtures thereof.
 6. A method according toclaim 5 wherein the mole ratio of compound (a) to cobalt(II) compound isfrom about 5 to about 5,000.